Mapping electoral outcomes

This Election Atlas provides background for understanding the 2013 mayoral election in New York City. It helps you visualize where the votes will come from and who is more likely to receive them. It particular, it visualizes election results for all the Democratic mayoral candidates who have previously run for citywide office. For comparison and contrast, it also includes maps of recent gubernatorial and presidential elections.

Recent primary, runoff, and general elections for Mayor, Comptroller, and Public Advocate show us how 4 of the 8 candidates fared in the past. These voting patterns provide a quantifiable, visual record against which to gauge the 2013 campaigns.

Fine-grained maps

Voting data is presented here in a new way — by Census block, instead of election districts. The City currently has about 5,300 election districts, but 30,000 inhabited city blocks. Displaying the information at this level reveals voting patterns literally city block by block in some areas, whereas election districts (EDs) often cover much larger areas. Census blocks also enable us to compare voting outcomes directly with Census demographics. And blocks provide a common geographic unit for comparing elections consistently across time, even when ED boundaries change.

To allocate ED-level voting results to blocks, the Center for Urban Research geocoded more than 11 million voter registration records over the past eight years to determine how those actually casting ballots each year overlap between EDs and blocks. See the Methodology section in the More... tab above for details.

Vote share & turnout

The different colors on each map depict the winners and losers. The shade of each block's color represents how strongly voters supported the candidate, while the intensity of the colors portrays the level of turnout. This enables you to understand not only how strongly voters in a given area favored the candidate, but also how well each candidate mobilized their voter base to come to the polls.

Each map can also be viewed in relation to demographic patterns, neighborhoods, and Council districts. Use the dynamic overlays above each map:

We provide a summary analysis next to each map about each election, and we encourage you to examine the maps closely to reach your own conclusions.

2014 Gubernatorial Election

This page analyzes the results of the 2014 election for governor on a statewide basis & how the vote patterns compare with the election in 2010. (Click the "General (2014)" tab above to view local gubernatorial vote results in NYC, as well as maps of results in the 11th Congressional district.)

Summary Analysis

Governor Andrew Cuomo — a popular Democrat whose campaign touted his progressive credentials — was re-elected in 2014. But the statewide electoral results this year were hardly an extension of the progressive victory by Mayor Bill de Blasio in NYC a year earlier.

Although Republican candidates lost all 3 statewide offices in 2014 (Governor, Attorney General, & Comptroller), Republicans prevailed in other important ways. Cuomo's Republican opponent came closer than many expected (Rob Astorino received 40% of the vote while Cuomo received only 53%), Cuomo won in NYC but lost the rest of the state (the map at right shows the counties Cuomo lost shaded in orange & red), Republican legislative candidates won in several races where Mayor de Blasio campaigned for their opponents, and Republicans regained majority control of the State Senate.

Whether these results reflected nationwide trends or the mood of a dwindling New York electorate, the 2014 election emboldened conservative forces in New York. With a Republican-controlled State Senate, a strengthened Democratic majority in the State Assembly, and a Governor perceived as electorally weaker than in his first term, legislative gridlock (or the capital's trademark legislative dealmaking) will likely return to Albany.

Summary Analysis

Rep. Michael Grimm handily won re-election in Nov. 2014 to City Councilmember Dominic Recchia by a 13-point margin (53% to 40%), despite the cloud of a federal indictment. The orange and dark red areas on the map show the strength of Grimm's electoral support along Staten Island's south shore, while the blue areas on the island's north shore and in Brooklyn represent neighborhoods where Recchia received strong vote support.

Two months after the election, Grimm pleaded guilty to a federal charge of tax evasion, and resigned his seat in January 2015. Gov. Cuomo has set a special election for District 11 for May 5, 2015. Staten Island District Attorney Dan Donovan is the GOP candidate for the district; no Democratic candidate has been selected (as of 2/20/15).

Enrollment in the district is plurality Democratic (just over 47% in 2014, compared with 26% Republican and 21% not enrolled in any party). More than twice as many registered voters live on Staten Island (265,000) than in the Brooklyn portion of the district (115,000), but even on Staten Island alone, enrollment is 45% Democratic compared with 29% Republican. Despite Rep. Michael Grimm winning the last two Congressional races, other Democrats have won the district in recent years, as these maps reveal.

Summary Analysis

Bill de Blasio scored a substantial victory in the 2013 mayoral race, winning 73.3% of the vote vs. 24% for Joe Lhota, a 49 point margin. It is also historic, since he will be the first Democrat to be mayor in almost 20 years. Perhaps because the race was so lopsided, turnout was low, about 1 million votes cast at polling places.

This map shows that he received solid support throughout the city, with some important exceptions. His Republican opponent Joseph Lhota won the traditionally Republican-leaning Upper East Side, some of the orthodox Jewish communities in southern Brooklyn, Middle Village and other areas in northeast Queens, and Staten Island's white Catholic south shore (Lhota won the vote in Staten Island overall).

City Councilmember Letitia James won the runoff with just under 60% of the vote, against State Senator Daniel Squadron. Turnout was relatively low — almost 188,000 votes cast, or roughly 6% of registered Democrats. By comparison, turnout in the 2009 runoff for Public Advocate was just over 230,000 votes, and in 2001 the Public Advocate's runoff election brought out almost 670,000 voters (in part due to the mayoral runoff election that year).

The slider above the map at right reveals predominant race/ethnicity patterns compared with the vote results (and the drop-down list will show other demographic patterns). The interactive map available by clicking the "Public Advocate runoff" tab above enables you to click on the map to reveal actual vote counts, vote share, and turnout percents in each Election District.

Summary Analysis

James received solid support — measured by vote share and turnout — in the largely African American and Afro Caribbean areas of central Brooklyn, southeast Queens, and Central Harlem, as well as Wakefield in the Bronx, much of the south Bronx, and along Staten Island's north shore (albeit with lower turnout). She also did well in predominantly white areas in and around Park Slope.

Squadron did well in the Upper East Side, lower Manhattan, orthodox areas of Brooklyn, Riverdale, and much of the rest of Staten Island. Notably, James received solid support across her entire City Council district (#35, outlined in blue on the map), while support for Squadron from his State Senate district (#26, outlined in dark gray) was much more mixed.

Bill de Blasio's victory in the Democratic primary was suprising to many, partly because he was an early underdog candidate in a crowded field (eight other candidates including the former NYC Comptroller who also ran for mayor in 2009 and almost won, the current Comptroller, City Council speaker, and a high profile former Congressman).

But most observers also assumed the city's Democratic voters would largely follow earlier electoral patterns of "identity politics" in which black voters would support William Thompson, the former comptroller and an African American, recent immigrants would support John Liu, the current comptroller and an immigrant himself from Taiwan, and native-born whites of various ethnicities and ancestries would split their vote among de Blasio, Christine Quinn, Anthony Weiner, and perhaps several of the lower profile candidates.

De Blasio's support (more than 260,000 votes) was widespread and seemed to run counter to the "identity politics" narrative. In particular, it exceeded Thompson's support in predominantly black communities where Thompson himself did well in 2009. At the same time, Liu's support was limited to communities with predominantly Chinese and other Asian populations (an example of identity politics, but backed up with relatively few votes — just under 45,000). And Quinn (99,700 votes) and Weiner (just over 31,000 votes) received fewer votes combined than Thompson (168,000).

The maps on this page highlight these patterns and explore the variations within.

Summary Analysis

This map shows de Blasio's support citywide, along with areas where he did not do well.

The map highlights the areas where his victory was unexpected — the dark green areas in central Brooklyn (predominantly African American and Afro Caribbean neighborhoods), southeast Queens along the Nassau County border (also mainly Afro Caribbean), and the West Village in Manhattan which Quinn represents in the City Council. De Blasio also received support, though not as strong (indicated by lighter green on the map), in Harlem, upper Manhattan, and Staten Island's north shore.

Combined with de Blasio's traditional base of support in Brownstone Brooklyn plus "white ethnic" communities such as Greenpoint and Long Island City, these areas gave him his victory in the primary.

But the map also reveals key areas voting against de Blasio (highlighted in red or orange), such as Orthodox Jewish communities in south Brooklyn, Hasidic Williamsburg, Manhattan's Upper East Side, much of the rest of Staten Island, and many areas of Queens. These communities all turned out heavily in support of Michael Bloomberg in the 2001, 2005, and 2009 general elections. This year's general election outcome will depend in part of lower turnout in these areas and stronger turnout in areas where de Blasio did well in the primary.

Summary Analysis

In the June 2014 congressional primaries, longtime incumbent Charles Rangel faced a rematch of the campaign two years earlier, when Rangel narrowly defeated State Senator Adriano Espaillat. Espaillat ran again but lost in another close race: Rangel received 47%, Espaillat received almost 44%, and the remaining votes were split by two lesser known candidates.

The 2014 primary vote results, mapped here, show a vote pattern very similar to the 2012 race. Cong. Rangel did well in his longtime base of Central & East Harlem (the election districts shaded in orange and dark red on the map).

Rangel lost most of the EDs in Washington Heights and Inwood (shaded in yellow and light orange), located in State Senate district 31 represented by Espaillat. He also lost most — though not all — of the EDs in the Bronx section of CD13, which had been added during the 2012 redistricting cycle.

Summary Analysis

In June 2012, then-21-term congressman Charles Rangel narrowly won the Democratic primary by a 1,086 vote margin against State Senator Adriano Espaillat and three other challengers. This year, Congressman Rangel again faces Senator Espaillat as well as two other new challengers in another contentious primary election.

The 2012 primary vote results, mapped here, offer a recent view of the district's local electoral patterns. Cong. Rangel did well in his longtime base of Central & East Harlem (the election districts shaded in green on the map) — though only a handful of EDs in Harlem gave him solid support (the dark green EDs with more than 75% of the vote).

Rangel lost most of the EDs in Washington Heights and Inwood (shaded in orange and red), located in State Senate district 31 represented by Espaillat. He also lost most — though not all — of the EDs in the Bronx section of CD13, which had been added during the 2012 redistricting cycle.

Summary Analysis

William Thompson won the 2009 mayoral primary with 71 percent of the vote against a Queens-based Italian-American in second place. His base reflected the classic Democratic coalition — African American and Latino minority neighborhoods and the white liberal areas stretching from Park Slope up through the Village and West Sides in Manhattan up through Riverdale in the Bronx.

However, turnout was not high and he received support in many areas that subsequently voted strongly for Mayor Bloomberg in the general election, including Park Slope, the Upper East and West Sides, and Riverdale.

Summary Analysis

Thompson lost the 2009 general election to Mayor Bloomberg in 2009 by only 4.4 percentage points, an unexpectedly close margin. This map reveals where Thompson got the largest share of votes with strong turnout (deepest blue) but also where voters favored him at similar levels, but did not turn out at equally high levels (light blue). Perhaps energizing more voters in these latter areas would have altered the outcome for Thompson.

High support, high turnout areas voting for Thompson are relatively sparse compared to support for certain other Democratic general election candidates (for example President Obama in 2012) and are found in southeast Queens, Central Harlem, and parts of central Brooklyn. Communities who voted strongly in favor of Thompson but had lower turnout surrounded these areas of intense support in Harlem, Central Brooklyn, and Southeast Queens, and included virtually all of the south Bronx.

Some communities supported Thompson in the primary but voted instead for Bloomberg in the general election, including the East and West Sides of Manhattan and the Village (but not the Lower East Side), Brownstone Brooklyn and the Southern part of the borough, Riverdale, and parts of Staten Island's north shore.

The purpose of these two maps is to show how strongly one African American candidate, Barack Obama, won the 2008 general election, while a second, William Thompson, had much more partial support only one year later in 2009. In short, many areas that were willing to support a black Democratic nominee for high office in one year shifted to the incumbent Mayor, running on the Republican and Independence lines, in 2009.

Summary Analysis

The 2008 presidential election was historic, as the nation elected its first black chief executive. Candidate Obama won almost 80 percent of the vote in New York City, losing only in Staten Island but winning the other four boroughs, the Bronx by almost 90 percent. More than 2.6 million people turned out to vote, a record high.

The Obama vote generally followed enrollment patterns, with only the solidly Republican areas of Staten Island and south Brooklyn voting for Republican John McCain.

Summary Analysis

The Democratic primary for mayor in 2001 was scheduled for September 11. The terrorist attack on the World Trade Center prompted all candidates in the primary to suspend campaigning, and the city's Board of Elections postponed the primary vote till Sept. 25, two weeks later.

The lackluster campaigns till then had pitted four prominent Democrats: Mark Green, a white left-leaning Democratic and former city Public Advocate (largely favored in Manhattan); Fernando "Freddy" Ferrer, a Latino leader who was Bronx Borough President at the time; Alan Hevesi, the sitting City Comptroller (from Queens); and Peter Vallone, Sr., the sitting City Council President (also from Queens).

Ferrer and Green were the front-runners in the race. On the rescheduled primary day, Green received just 31% of vote (243,182 votes out of 785,365) — mainly from the traditionally liberal neighborhoods of Park Slope, Greenwich Village & Chelsea, the Upper West and Upper East sides, and Riverdale in the Bronx, plus scattered support in central Brooklyn and southeast Queens — while Ferrer received 35% (279,451 votes out of 785,365), prompting a runoff.

Summary Analysis

This map shows where Thompson improved the Democratic vote over Ferrer in 2005 and Green in 2001 in largely Democratic areas (southeast Queens, Central Brooklyn, upper Manhattan, and much of the Bronx), and to a lesser extent where Thompson made inroads into Bloomberg's areas of support such as Riverdale and eastern Bronx, parts of Queens, and the Bay Ridge area in Brooklyn.

These electoral shifts helped Thompson but were not enough: Thompson lost the 2009 general election to Mayor Bloomberg by only 4.4 percentage points, an unexpectedly close margin (Thompson received 534,869 votes out of 1,137,625; while Bloomberg received 585,466).

These maps show that Thompson was not the only candidate for top office to do less well than Barack Obama in 2008. Indeed, Obama himself did less well in 2012 than he had in 2008, while Democratic gubernatorial nominee Andrew Cuomo also did less well. At the same time, these maps show that voting in elections for chief executive of the state and country has a different make-up than voting for the city's chief executive.

Summary Analysis

While only 2.45 million votes were cast in the 2012 presidential election, compared to 2.62 million in 2008, this election was another high point for voter turnout out in New York City. Also, though turnout in 2012 was less than in 2008, it still drew many more voters than any mayoral election. Turnout fell relatively more in the Latino areas of the city, while the margin shifted against the President most in the Orthodox/Hasidic neighborhoods.

The vote pattern was almost exactly the same as in 2008. The President's highest margins were in the areas with greatest Democratic enrollment. He lost in only a few areas, including the ultra-Orthodox neighborhoods of Borough Park and Williamsburg (though the anti-Obama turnout in that area of Williamsburg was lower in 2012 than in 2008).

Summary Analysis

Voting patterns in New York City elections often follow predominant race/ethnicity patterns — but not always. This map shows the geographic concentrations of the city's population along race/ethnicity/ancestry lines to compare and contrast with voting outcomes.

The most basic racial categories include whites, blacks, Hispanics, and Asians (New York City has comparatively few native Americans). While the Census does not (yet) consider Hispanics to be a race — and currently provides them with the option of choosing any race — in practice, many Hispanics choose to categorize themselves as an "other" race. Demographers and the person on the street tend to unite in classifying all Hispanics as a distinct group and separating them from the other racial groups. However, these four groups are clearly too broad a classification. Each of these groups is characterized by important differences relating to ethnicity or national origin, nativity (i.e. native born or immigrant), and religion.

Whites can therefore be broken down into a number of major components, including white Catholic groups (primarily Italians and Irish), Jews (further distinguished by degree of religiosity), and secular whites. Similarly, blacks may be broken down into African Americans, Afro Caribbeans, and Africans; Hispanics include Puerto Ricans, Dominicans, Mexicans, Colombians, Ecuadorans, and so on; and Asians include Chinese, Koreans, Indians, Bangladeshis, and Filipinos.

Of course, while black–white segregation remains quite high in New York City, and Hispanics and Asians also live at lower but still significant levels of spatial concentration, groups overlap and intermix and many neighborhoods in New York City have a fairly heterogeneous makeup. So neighborhoods and communities cannot be equated with racial–ethnic groups. Still, one or two groups tend to predominate in any given neighborhood.

How we analyzed the data

In order to visualize the patterns of voting results from 2001 to 2012 at the local level across the city, we used the smallest geographic area possible. The NYC Board of Elections records local voting results by Election District. There are currently almost 5,300 election districts covering the city with an average population of 1,500 people. (In comparison, Census tracts are larger – there are 2,100 tracts with an average of 3,700 people – and Census blocks are much smaller – there are approximately 30,000 populated blocks with an average population of less than 300.)

But election district (ED) boundaries change each year, especially after redistricting. In 2010, for example, there were 6,300 EDs. By 2012 that number had dropped to less than 5,300. Therefore we could not directly compare the vote counts by ED from one year to the next. Also, election district boundaries are not coterminous with Census geography, making it difficult to directly compare vote results to demographic data reported by Census tract or block.

Allocating from EDs to Census blocks

Therefore, we decided to allocate ED-level vote counts to Census blocks. This provides an apples-to-apples spatial comparison of the local voting patterns from one year to the next, and also allows for easy analysis of voting patterns with Census data.

Allocating population data (in this case, voting population) from one type of geography to another can be accomplished using several methods. This is a common practice with redistricting, when voting data by precinct needs to be allocated to Census blocks, which are literally the building blocks of legislative districts.

The methodology we used was to determine the proportion of each ED's population that was located in each overlapping area between EDs and Census blocks. If an ED was wholly contained within a block, 100% of the votes from the ED were allocated to the block. If 50% of the ED overlapped a block, only half the votes were allocated to the block.

This effort was more involved than other attempts to allocate population from one geography to another. First, we wanted to allocate the voting results from at least eight years worth of election districts to the current (2010) Census blocks. We allocated the results from elections from 2001 to 2012 (with the exception of the few years when there were no citywide elections of significance). We included primary (and runoff) elections and general elections for Mayor, Comptroller, and Public Advocate at the city level, and Governor and President at the state and federal levels – we wanted to focus on executive offices (consistent with analyzing the race for mayor).

Two other factors adding to the complexity of the allocation process were the number of candidates and the population base that we used to determine the overlap between EDs and Census blocks. All told, we allocated voting results for more than 40 candidates. In 2009 alone there were 13 major-party candidates for the elections noted above.

Regarding the overlap between EDs and blocks, there are several approaches that are typically used. Our approach was to determine the number of voters registered in each year we examined, and use each ED's count of registered voters as the denominator and the number of active registered voters in each overlapping area between EDs and blocks as the numerator. If five voters were located in an overlapping area, and the ED's voting population was 25, twenty percent of the ED's votes in that year for each candidate were allocated to the overlapping block. The results of those calculations were then summed by block, for each candidate in each election in each year, to determine the block-level totals.

(As an aside, each year's ED boundaries from the Bytes of the Big Apple program had to be cleaned using ArcMap's "repair geometry" tool before comparing the ED geometry with Census blocks. Otherwise, the allocation results were bing confounded by stray, seemingly random and invisible ED boundaries. The Repair Geometry tool removed these phantom EDs and the subsequent results were internally consistent and sensible.)

The schematic outline below summarizes the allocation process using EDs and tracts:

Geocoding 18 million records

To determine the exact count of voters in each overlapping area, we geocoded each year's active registered voters from registration files provided by the NYC Board of Elections. Although there were duplicate records from year to year (people who remain registered at the same address from one year to the next), we needed a separate population base for each year's voting results. Therefore, we geocoded more than 18 million voter registration records over the period from 2001 to 2012. We successfully matched more than 99% of these records, due to the address quality in the Board of Election files and our geocoding system refined over several years of use with city data.

Mapping vote results and turnout

Maps of election district results tell only part of the story of electoral outcomes. Without also accounting for voter turnout, choropleth maps that just show voting results treat all outcomes as equal (in terms of color intensity), and ignore the importance of a candidate's ability to turn out his/her base of support.

After testing different color styles and cartographic techniques, CUR used the value-by-alpha approach that uses color to indicate value (in this case, a candidate's share of votes) and levels of transparency of those colors (the "alpha" component of a color scheme) to indicate intensity of that vote share as measured by turnout.

Calculating turnout.

Credits

Data

The Center for Urban Research obtains election data from the NYC Board of Elections and uses SPSS to restructure the files into a database format suitable for analysis. The Board of Elections provides election results by Election District (ED), and all registered voters citywide.

CUR's John Mollenkopf, Steven Romalewski, and Kristen Grady worked together to develop a methodology to allocate ED results to Census blocks (see Methodology section). Steven geocoded the voter registration records for active voters to develop a voter population base for the allocation process. Kristen, a PhD student in Earth and Environmental Science at the CUNY Graduate Center, used ESRI's ArcGIS for Desktop to allocate the ED-level results to Census blocks. The allocation is a tedious and painstaking — but essential! — multi-step process involving several spatial calculations comparing each year's ED boundary file (typically 5,000 to 6,000 ED polygons) with the 2010 Census block file (almost 40,000 polygons) and attribute calculations for each candidate in each year's elections. So Kristen developed a set of Python scripts and ArcMap modules to automate the process of allocating ED data to blocks for each of the candidates in each year's primary, runoff, and general elections (more than 40 candidates between 2005 and 2012).

Maps

CUR's Romalewski produced the maps with ArcGIS for Desktop based on a technique developed by Andrew Wheeler, a PhD student at the University at Albany, SUNY. Other cartographers and election analysts offered very helpful feedback along the way.

Partners

The CUNY Graduate School of Journalism and its Center for Community and Ethnic Media have partnered with the Center for Urban Research at the Graduate Center / CUNY to develop the Atlas. The Journalism School and CCEM have provided generous funding support to provide public access to the Atlas's maps and data and to ensure that Journalism School students and CCEM media outlets benefit directly from this work.

The Graduate Center's information technology team and communications and marketing staff have provided essential support for the project.